[lld] [lld][WebAssembly]: Avoid emitting empty __wasm_apply_data_relocs function (PR #109249)

[Sam Clegg via llvm-commits]

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@@ -378,7 +378,7 @@ void InputChunk::generateRelocationCode(raw_ostream &os) const {
     uint64_t offset = getVA(rel.Offset) - getInputSectionOffset();
 
     Symbol *sym = file->getSymbol(rel);
-    if (!ctx.isPic && sym->isDefined())
+    if (!ctx.isPic && !sym->hasGOTIndex())
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sbc100 wrote:

I'm finding this clauses a little hard to grok without a lot of introspection.

Maybe we could add a comment here?  Something like:

`// Runtime relocations are needed when we don't know the address of a symbol statically.`

Or better still, we could add a variable to make it more clear what is going on:

```
bool requiresRuntimeReloc = ctx.isPic || sym->hasGOTIndex();
if (!requiresRuntimeReloc)
   continue;
```   

https://github.com/llvm/llvm-project/pull/109249